1. Field of the Invention
This invention relates generally to wind shear warning instruments, and more particularly to wind shear warning instruments that provide an advisory message to a pilot upon the occurrence of a condition indicating that a wind shear is probable.
2. Description of the Prior Art
Various wind shear warning systems are known. Typical prior art systems are disclosed in U.S. Pat. Nos. 4,725,811 and 4,891,642 and in U.S. patent application Ser. No. 07/034,807, filed Apr. 3, 1987, now U.S. Pat. No. 4,905,000 all assigned to the same assignee as the assignee of the present invention.
While the systems described in the above-mentioned patents and application do provide a wind shear indication, the systems described in the above mentioned patents are designed not to respond to low level wind shears in order to avoid nuisance warnings, and consequently, can detect a wind shear only after a wind shear situation of a predetermined magnitude has been encountered. The system described in the above-referenced application does not require that a wind shear of a particular magnitude be encountered before a warning is generated, but predicts the probability of a wind shear based upon geographic position and temperature and barometric pressure conditions, and permits warnings to be generated earlier upon the occurrence of a condition where wind shear is more probable.
While the above-described systems do provide a way to provide wind shear warnings based upon the magnitude of the wind shear alone or in conjunction with other parameters, there are parameters other than those disclosed in the systems discussed above that can be monitored to indicate the probability of a wind shear.